The subject matter disclosed herein relates to a multi-stage centrifugal fan.
Fan designs are often constrained by envelope size requirements, rotational speed requirements, weight requirements and power requirements. Meanwhile, aerodynamic performance and motor electrical performance of fans are heavily influenced by these factors and, in particular, rotational speed of the fan. Thus, if improved aerodynamic performance is required of a fan but the fan is already operating at a practical limit for its rotational speed due to motor performance characteristics, fan design improvements may be required.
It is often the case, however, that envelope size requirements are stringent and, as such, there may not be room or space available for a larger fan design for a given fan application. Given that pressure rise requirements (i.e., a higher delta P) keep growing for certain fan applications and a way to ordinarily accommodate a higher delta P is to spin the fan faster or grow the fan rotor diameter, a new manner of accommodating a higher delta P may be beneficial.